Time Zone Converter
Enter a date and time in one time zone and see what it is in another, how many hours apart the two are, and the same moment across a board of common cities. Daylight saving is applied using the zone rules for that exact date.
Enter your details above — results update as you type.
Formula and calculation
Worked example
At 09:00 on January 15, 2026 in New York, the time in London is 14:00 on January 15, 2026 — 5 hours ahead. In January both cities are on standard time, so the gap is the full five hours.
Why the difference changes twice a year
Time zones are defined by offset from UTC, not by how far apart two cities are, and daylight saving is a local decision that shifts the offset by an hour. That is why the New York to London gap is five hours for most of the year but four hours from mid-March to late March and again from late October to early November, when one side has changed its clocks and the other has not. Countries also change their DST rules from time to time, and a few have abandoned the practice altogether, so any converter is only as current as the zone database behind it. This one reads the zone data built into your browser.
What the results mean
- Converted time
- The same moment expressed as a local clock time in the To zone. Check the date beside it — the hour can belong to the day before or after.
- Local date
- The calendar date in the To zone, which differs from your starting date whenever the conversion crosses midnight.
- Time difference
- How far ahead or behind the To zone runs compared with the From zone on this date. Half-hour zones such as India (+5:30) give a half hour here, and daylight saving on either side changes it during part of the year.
- New York UTC offset (hours)
- The From zone's offset from UTC in hours on this date. Negative means west of Greenwich, positive means east.
- London UTC offset (hours)
- The To zone's offset from UTC in hours on this date.
- Daylight saving
- Whether each zone is on daylight saving time on the chosen date — the reason a conversion can be an hour different from what you remember.
Frequently asked questions
How do I convert a time from one time zone to another?
Work in UTC: subtract the first zone's offset, then add the second zone's. 09:00 in New York (UTC−5) is 14:00 UTC, which is 14:00 in London (UTC+0) and 23:00 in Tokyo (UTC+9). Offsets like India's +5:30 keep the half hour, so IST is always two and a half hours ahead of the UTC-plus-3 zones.
What is the time difference between New York and London?
Five hours for most of the year, London being ahead. It narrows to four hours while the two sides disagree about daylight saving — in 2026, roughly March 8 to 29 and October 25 to November 1 — because one city has changed its clocks and the other has not yet.
What happens to a time that does not exist because of daylight saving?
In the hour skipped by a spring-forward change — 02:30 on a day when clocks jump from 02:00 to 03:00 — there is no such local time. This converter resolves it to the same minute one hour later, which is the convention most time zone libraries use. Meetings scheduled by mistake in that hour are a classic source of missed calls.
Does the converter use my computer's time zone?
No. It only uses the two zones you pick, plus the time zone rules that ship with your browser. Your own location matters only for the default date, which starts at today.
Is UTC the same as GMT?
For everyday purposes, yes — both are zero offset and the terms are used interchangeably in timestamps. Strictly, GMT is a time zone (with the UK's daylight saving rules attached in summer) and UTC is the modern atomic-time standard the whole offset system is defined against. Neither observes daylight saving.